Ribonucleic acid (RNA) plays an essential role in the translation of the genetic code to produce proteins necessary for cellular function, both in normal cells and neoplastic or diseased cells. In particular, RNA including transfer RNA, messenger RNA or messenger-like RNA, and ribosomal RNA carry and translate the genetic code to sites of protein production. Further, double-stranded RNA plays an important role in silencing genetic expression. Other RNA species are found within ribonucleoproteins. For example, telomerase RNA is a critical component of telomerase, an important ribonucleoprotein highly expressed in most cancers. The pathogenesis and regulation of cancer is thus dependent upon RNA-mediated translation of specific genetic code, often reflecting mutational events or other alterations within deoxyribonucleic acid (DNA), including epigentic alterations such as hypermethylation, microsatellite alterations, loss of heterozygosity, translocations, deletions, and point mutations. Further, other RNA species and their associated proteins, although not necessarily being directly involved in neoplastic pathogenesis or regulation, may provide recognizable characterization of neoplasia or disease by being inappropriately expressed or elevated. Such overexpression of RNA thus can delineate cancer or other disease. Recognition of the presence or overexpression of specific RNA can enable identification, detection, inference, monitoring, or evaluation of any neoplasm, whether benign, malignant, or premalignant, in humans and animals.
U.S. Pat. No. 6,329,179 B1, incorporated herein in its entirety, teaches that both tumor-associated and non-tumor associated RNA are detectable in plasma and serum. Total RNA, to be understood in cancer patient to comprise both tumor-associated and non-tumor-associated RNA and further being heterogeneous RNA, can be extracted from plasma or serum, the RNA of interest or its cDNA is amplified qualitatively or quantitatively, and the amplified product of an RNA or cDNA species of interest detected. Of particular note, U.S. Pat. No. 6,329,179 B1 teaches that extracellular RNA is present in greater amount when obtained from cancer patients than from healthy individuals, Subsequent art supports these teachings by demonstrating that extracellular RNA of various RNA species are detectable in bodily fluids, for example in co-owned U.S. Pat. No. 6,607,898; Kopreski et al., 1999, Clin. Cancer Res. 5: 1961-1965; Dasi et al., 2001, Lab, investigation 81: 767-769; Hasselmann et al., 2001, Oncol. Rep. 8: 115-118; Ng et al., 2002, Clin, Chem. 48: 1212-1217; Chen et al., 2000, Clin. Cancer Res. 6: 3823-3826; Silva et al., 2001, Clin. Cancer Res. 7: 2821-2825; Silva et al., 2001, Oncol. Rep. 8: 693-696; Gal et al., 2001, Ann. NY Acad. Sci. 945: 192-194; Durie et al., 2000, Acta Oncol. 39: 789-796; Fleischhacker et al., 2001, Ann. NY Acad. Sci. 945: 179-188; Miura et al., 2003, Oncology 64: 430-434; and Kopreski et al., 2001, Ann. NY Acad. Sci, 945: 172-178, said references incorporated herein in their entirety. Detection of tumor-associated RNA in plasma or serum thus provides a method for detecting, diagnosing, inferring, or monitoring cancer or premalignancy in a human or animal.
Thus, extracellular total RNA is increased in the plasma, serum, or other bodily fluid of humans or animals with cancer and other disease. Thus, there is a need in the art for methods of comparing the amount or concentration of plasma or serum total RNA, including both tumor and non-tumor related RNA, in a subject to that of healthy individuals, to permit diagnosis, detection, inference, or monitoring of diseases such as cancer in a human or animal that are associated with increased extracellular total RNA in said bodily fluids. Further, there is a need for methods comparing the amount or concentration of either total extracellular RNA or non-tumor extracellular RNA species or tumor-related extracellular RNA species from a bodily fluid to that in a healthy individual for diagnosing, detecting, inferring, or monitoring cancer and other neoplastic diseases in a human or animal.